This invention relates to a mining method and more particularly to the electrical sequential initiation of explosions in mining operations. The invention also concerns initiating means for use in such a system.
The accurate sequencing of explosions in underground mining operations is of the utmost importance. In advancing a tunnel or stope, sequential blasting is used to ensure that rock is moved in the required direction and to achieve efficient "chiselling" of the rock mass. Both out-of-sequence blasts and misfires can accordingly have significant adverse effects on mining production.
In an electrical sequential initiation system, initiating means may be used to initiate delay elements sequentially according to the sequence of explosions required. Once the delay element has performed its delay function, the explosive charge with which it is associated is detonated.
There is no technical barrier to providing an electrical sequential initiation system of this kind. However, in the mining industry such a system will only be viable if it can be produced at low cost.
It is accordingly an object of the invention to provide an electrical sequential initiation system which is of relatively simple configuration and which can be produced at relatively low cost.